package com.spice.im;

import java.util.Random;  

import android.graphics.Bitmap;  
import android.graphics.Canvas;  
import android.graphics.Color;  
import android.graphics.Paint;  
import android.graphics.Bitmap.Config;  
  
public class BPUtil {  
      
    private static final char[] CHARS = {  
        '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',  
        'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',   
        'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',  
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',   
        'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'  
    };  
      
    private static BPUtil bpUtil;  
      
    public static BPUtil getInstance() {  
        if(bpUtil == null)  
            bpUtil = new BPUtil();  
        return bpUtil;  
    }  
      
//  width="60" height="30"   
//          base_padding_left="5"  
//          range_padding_left="10"  
//          base_padding_top="15"  
//          range_padding_top="10"  
//          codeLength="4"  
//          line_number="3"  
//          font_size="20"  
      
    //default settings  
    private static final int DEFAULT_CODE_LENGTH = 6;  //4
    private static final int DEFAULT_FONT_SIZE = 35;  //20
    private static final int DEFAULT_LINE_NUMBER = 1;  //3
    //5,10,15,10
    private static final int BASE_PADDING_LEFT = 10, RANGE_PADDING_LEFT = 20, BASE_PADDING_TOP = 25, RANGE_PADDING_TOP = 10;  
    private static final int DEFAULT_WIDTH = 200, DEFAULT_HEIGHT = 50;  //60,30
      
    //settings decided by the layout xml  
    //canvas width and height  
    private int width = DEFAULT_WIDTH, height = DEFAULT_HEIGHT;   
      
    //random word space and pading_top  
    private int base_padding_left = BASE_PADDING_LEFT, range_padding_left = RANGE_PADDING_LEFT,   
            base_padding_top = BASE_PADDING_TOP, range_padding_top = RANGE_PADDING_TOP;  
      
    //number of chars, lines; font size  
    private int codeLength = DEFAULT_CODE_LENGTH, line_number = DEFAULT_LINE_NUMBER, font_size = DEFAULT_FONT_SIZE;  
      
    //variables  
//    private String code;  
    private int padding_left, padding_top;  
    private Random random = new Random();  
      
    public Bitmap createBitmap(String code) {  
        padding_left = 0;  
          
        Bitmap bp = Bitmap.createBitmap(width, height, Config.ARGB_8888);   
        Canvas c = new Canvas(bp);  
  
//        code = createCode();  
          
        c.drawColor(Color.WHITE);  
        Paint paint = new Paint();  
        paint.setTextSize(font_size);  
          
        for (int i = 0; i < code.length(); i++) {  
            randomTextStyle(paint);  
            randomPadding();  
            c.drawText(code.charAt(i) + " ", padding_left, padding_top, paint);  
        }  
  
        for (int i = 0; i < line_number; i++) {  
            drawLine(c, paint);  
        }  
          
        c.save( Canvas.ALL_SAVE_FLAG );//����    
        c.restore();//  
        return bp;  
    }  
      
//    public String getCode() {  
//        return code;  
//    }  
      
    private String createCode() {  
        StringBuilder buffer = new StringBuilder();  
        for (int i = 0; i < codeLength; i++) {  
            buffer.append(CHARS[random.nextInt(CHARS.length)]);  
        }  
        return buffer.toString();  
    }  
      
    private void drawLine(Canvas canvas, Paint paint) {  
        int color = randomColor();  
        int startX = random.nextInt(width);  
        int startY = random.nextInt(height);  
        int stopX = random.nextInt(width);  
        int stopY = random.nextInt(height);  
        paint.setStrokeWidth(1);  
        paint.setColor(color);  
        canvas.drawLine(startX, startY, stopX, stopY, paint);  
    }  
      
    private int randomColor() {  
        return randomColor(1);  
    }  
  
    private int randomColor(int rate) {  
        int red = random.nextInt(256) / rate;  
        int green = random.nextInt(256) / rate;  
        int blue = random.nextInt(256) / rate;  
        return Color.rgb(red, green, blue);  
    }  
      
    private void randomTextStyle(Paint paint) {  
        int color = randomColor();  
        paint.setColor(color);  
        paint.setFakeBoldText(random.nextBoolean());  //trueΪ���壬falseΪ�Ǵ���  
        float skewX = random.nextInt(11) / 10;  
        skewX = random.nextBoolean() ? skewX : -skewX;  
        paint.setTextSkewX(skewX); //float���Ͳ������ʾ��б��������б  
//      paint.setUnderlineText(true); //trueΪ�»��ߣ�falseΪ���»���  
//      paint.setStrikeThruText(true); //trueΪɾ���ߣ�falseΪ��ɾ����  
    }  
      
    private void randomPadding() {  
        padding_left += base_padding_left + random.nextInt(range_padding_left);  
        padding_top = base_padding_top + random.nextInt(range_padding_top);  
    }  
}  
